Not everyone has the right kind of window to use a portable air conditioner. That’s certainly true in my apartment. So I decided to research and write this quick guide on using a portable AC without a window.
Can a portable AC work without a window?
Yes, a portable AC can work without a window. But a portable AC will need an alternative way to get rid of excess heat like a sliding door, dryer vent, or ceiling vent. All air conditioners generate heat and won’t cool down your home unless they have an efficient way of getting rid of it.
Most people think of portable air conditioners as a source of cold air. A better way of thinking about how portable air conditioners work is that they move heat out of your home.
A cooling element called an evaporator coil absorbs heat from your home into the cold refrigerant. That refrigerant then warms up and is compressed to increase its temperature. A fan then blows air over the heated condenser coil and out of your home.
So a portable air conditioner works like a conveyor belt of heat. It removes the heat from your indoor air and then transfers it to a stream of air that leaves your home via the exhaust tube.
The hot air needs to go somewhere but there are alternatives to running an exhaust tube out your window.
Why does a portable AC need a window?
A portable AC needs a window or another escape route for hot air in order to get rid of the heat it generates. Without some kind of exhaust, a portable AC would produce both hot and cold air and your home’s temperature wouldn’t change at all.
That’s why every kind of air conditioner has some way of getting hot air outside. Window AC units and portable ACs have the most obvious route because they just push the hot air out the window.
But the same principle applies to split ACs and in-wall ACs. Split ACs and in-wall ACs don’t move hot air out of your home. Instead, they move heat via a refrigerant pipe that moves the refrigerant from an internal unit and an external unit.
The external unit has all the components that deposit heat into the outdoor air. The hot compressor coil sits in the external unit and a fan circulates outdoor air over them.
If you walk past a building a see big grey boxes with fans in them mounted to the outside, those are external air conditioning units. You’ll feel a hot stream of air if you stand in front of them.
How to use a portable AC without a window?
You can use a portable AC without a window if you use a sliding door vent, ceiling vent, or through-wall vent. The portable air conditioner needs somewhere to get rid of hot air but there are alternatives to a window.
Here are the best alternatives to using a window with a portable air conditioner:
- Sliding door vent: You can attach a portable AC to a sliding door much like you would a window. Sometimes you’ll have to buy an extender to your window kit in order to get the exhaust tube to fit snugly to your sliding door.
- Ceiling vent: Using a ceiling vent is a popular option in office spaces which often have a false ceiling that houses a ventilation system (this will most likely be made of a bunch of styrofoam tiles). You can buy a ceiling vent kit that will fit into the ceiling.
- Wall vent: A good vent is a more permanent option. You might already have a vent through your wall that you can use. Otherwise, you’ll have to install one. Then, you can attach the portable air conditioner and pump hot air through your wall instead of through a window.
- Dryer vent: Another alternative is to use the dryer vent in your laundry room as a way to get rid of the excess heat generated by a portable air conditioner. The dimensions of a dryer vent are generally the same as a portable air conditioner wall vent. However, you may not want to mostly cool the air in your laundry room.
Mark is a journalist who has written about home products for two years. He holds a masters degree with distinction from the London School of Economics and an undergraduate degree from the University of Edinburgh.